Answer:
his is a multi-part question. Once an answer is submitted, you will be unable to return to this part. Air enters a nozzle steadily at 2.21 kg/m3 and 40 m/s and leaves at 0.762 kg/m3 and 192 m/s. The inlet area of the nozzle is 90 cm2.
determine (a) the mass flow rate through the nozzle, and (b) the exit area of the nozzle.
a)0.7956kg/s
b)5.437 × 10⁻³m²
Explanation:
The concepts related to the change of mass flow for both entry and exit is applied
The general formula is defined by

Where,

values are divided by inlet(1) and outlet(2) by


PART A) Applying the flow equation

PART B) For the exit area we need to arrange the equation in function of Area, that is

The pressure generated by the piston at the input cylinder must be:
p = F / A = 250 lb-f / 30 in^2
The pressure generated by the piston at the output cylinders is p = F / A = 775 lb-f / A.
Pascal principle rules that both pressures are equal, so:
250 lb-f / 30 in^2 = 775 lb-f / A => A = 775 lb-f * 30 in^2 / 250 lb-f = 93 in^2
Gvien that each output cylinder are 30in^2 you need 93 / 30 = 3.1 cylinders.
Which means that at least you need 4 cylinders to generate a force at least of 775 lb-f.
Answer: 4
Answer:
C 350W
Explanation:
Given power output to walk on a flat ground to be 300W, h = 0.05x, v = 1.4m/s
m = 70kg and g =9.8m/s².
x = horizontal distance covered
Total energy used = potential energy used in climbing and the energy used in a walking the horizontal distance.
E = mgh + 300t
Where t is the time taken to cover the distance
x = vt and h = 0.05vt
So
E = mg×0.05×vt + 300t
Substituting respective values
E = 70×9.8×0.05×1.4t +300t = 348t
P = E/t = 348W ≈ 350W.
Answer:
Explanation:
charge transferred to sphere = 12 - 8 = 4 nC
a )
The positive charge is decreased on glass rod , that means electrons must have entered the glass rod from the sphere which reduces its positive charge.
b )
charge transferred = 4 nC = 4 x 10⁻⁹ C
charge on one electron = 1.6 x 10⁻¹⁹ C
No of electrons transferred
= Total charge transferred / charge on one electron
= 4 x 10⁻⁹ / 1.6 x 10⁻¹⁹
= 2.5 x 10¹⁰ .